Audi TT Check Engine Light On with Codes 16486, 16684, 16687, 16688, 16685, 16825, P6686 on Audi TT

Some Audi TT owners report experiencing multiple fault codes that indicate various issues, such as boost pressure regulation problems (code 16486) and random or multiple cylinder misfires (code 16684). Additionally, owners may encounter specific cylinder misfires, including those in cylinders 1 (code 16685), 3 (code 16687), and 4 (code 16688). Another common issue involves the EVAP system leak detection pump sense circuit (code 16825). It is important for owners to methodically diagnose and address each fault code to resolve the underlying problems that trigger the check engine light. If issues persist, seeking assistance from a qualified mechanic or an Audi dealership is recommended for accurate diagnosis and repair.